DatabaseCacheTagsChecksum::calculateChecksum

protected DatabaseCacheTagsChecksum::calculateChecksum(array $tags)

Calculates the current checksum for a given set of tags.

Parameters

array $tags: The array of tags to calculate the checksum for.

Return value

int The calculated checksum.

File

core/lib/Drupal/Core/Cache/DatabaseCacheTagsChecksum.php, line 105

Class

DatabaseCacheTagsChecksum: Cache tags invalidations checksum implementation that uses the database.

Namespace

Drupal\Core\Cache

Code

protected function calculateChecksum(array $tags) {
  $checksum = 0;
 
  $query_tags = array_diff($tags, array_keys($this->tagCache));
  if ($query_tags) {
    $db_tags = array();
    try {
      $db_tags = $this->connection->query('SELECT tag, invalidations FROM {cachetags} WHERE tag IN ( :tags[] )', array(':tags[]' => $query_tags))
        ->fetchAllKeyed();
      $this->tagCache += $db_tags;
    }
    catch (\Exception $e) {
      // If the table does not exist yet, create.
      if (!$this->ensureTableExists()) {
        $this->catchException($e);
      }
    }
    // Fill static cache with empty objects for tags not found in the database.
    $this->tagCache += array_fill_keys(array_diff($query_tags, array_keys($db_tags)), 0);
  }
 
  foreach ($tags as $tag) {
    $checksum += $this->tagCache[$tag];
  }
 
  return $checksum;
}

Links:

https://api.drupal.org/api/drupal/core%21lib%21Drupal%21Core%21Cache%21DatabaseCacheTagsChecksum.php/function/DatabaseCacheTagsChecksum%3A%3AcalculateChecksum/8.2.x

doc_Drupal

2025-01-10 15:47:30

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